Jack ladder



Sept. 21 1926. 1,600,572 I M. BAUER JACK LADDER Filed Septh1'7, 1924 Patented Sept. 7 21, 1926.

MARTIN AUER, or oLEvELAiinoHiof 1 JACK LADDER.

Application filed-September 17,1924. Serial No. 738,131. Y

My invention relates to improvements. in jack ladders. This type ladder is designed especially for the use of painters when painting large surfa es such'as the side of 5 a building. With the-use of ordinary ladders, it is-necessary for thepainter ,to constantly change the position of the ladderLf Theordinary ladders are sometimes providedfwith jacks or supports hung tothe 10 rungs of the ladder for supporting a shelf upon'which the painter stands. Inthis case two or more ladders are utilized. Y I

lVith my invention these supports or jacks are permanently associated with the ladder and are arranged to'be folded up into a compact form so as not to protrude beyond the side rails of the ladder.

Various other features of my invention will be pointed out in the detailed description to ollow.

My invention is illustrated in the accom panying drawings wherein Fig, 1 is an enlarged front elevation of my invention; Fig. 2 is a side view with '2 one rail removed, parts being in section; Fig. 3 is an enlarged view of a portion of the supporting jack; and Fig. 4 is a sectional view of Fig. 3 on the line 4-4.

Referring to Figs. 1 and 2 the upper portion of the ladder is shown with the top supporting jack open ,for supporting a platform and the lower supporting jack folded up and locked in place. The extreme upper portions of the side rails are provided with the extension arms 70 each having a pointed projection 71 for engaging the surface 100. These supports, one being provided for each side rail are attached thereto by means of the brackets 6. The arms 70 are pivoted to 40 the brackets at 73. The brackets are attached to the side rails by means of the screws 7. Each bracket is provided with a supporting flange 72 within which the arm 70 slides as shown in Fig. 2. As shown in dotted lines, (Fig. 2) the arm assumes a downward position and may be held in place by buttons 4 or the like which by means of rivets 5 are attached to a cross piece 3 extending between the side'rails and serv- 59 ing as one run of the ladder; the usual ladder rungs being indicated at 2.

The movable portion of the supporting jack comprises a cross piece 13 having extension shafts 15 at the ends which engage openings or sockets in the brackets 60 in which it rotates. The cross piece 13 is providedwith a bracelet which is riveted therei to as'shown at 19. vAttached to this brace Hand the'cross piece. 13 by means of the rivets 7 3 lS an extension angle iron arm'35 wherev end is upturned to form a stop 18.

Attached to the angle iron arm :35 by means...

7 of the pivot 12 is anangle-iron brace 10.

This brace 10 is provided" with air-extension 11 for engaging the opening 30 in-the fixed cross piece 20 which is placed below'the This fixed cross rotatable cross piece .13. piece 20 is fastenedto theside'railrby means of the screws 26 and 2T. Additionalibraces '23 are provided as sliown'ifor giving additional support .to the cross piece 20. and

are fastened to the siderails 1 andgcross pieces 20 by screws 25 and bolts 24 respectively Alocking device 21 is pivoted at 31 to th'e'cross piece 20 .forflocking the brace 10 in place when the extension 11 engages the opening 30.

As shown in Fig. 3, this extension 11 is notched at 7 5 to receive the edge of the locking device 21. A latch or locking device 16 is pivoted to the cross piece 13 at 17 and a similar locking device 22 which is pivoted to the fixed cross piece 20 at 32 serves to lock the supporting jack when it is folded up as shown in the lower part of Figs. 1 and 2.;

The lower supporting ack shown in Figs. 1 and 2 is in its folded position, and in this position, the angle iron arm 35 is folded down until it comes in contact with the surface of the brace 20, after which the locking device 22 is turned untilit engages the projection 36, thereby holding the arm 35 locked against the fixed cross piece 20. The main supporting angle iron arm 10 is folded in an upward position until it comes in contact with the rotating cross piece 13, after which the locking device 16 is turned to engage the arm 10 and lock it in engagement with the fixed cross piece 20.

As before described, the arm 70 is folded downward as shown in Fig. 2 in dotted lines and is therefore locked in place protected by the side rails 1. f

When all of the supporting jacks are in their folded position, the ladder as a Whole is in a compact form and can be moved about without injuryto any of the working parts. I

It has been found in practice that when the top supporting jacks are mounted within five feet from the top of the side rails should be located not over seven feet from the bottom of the ladder.

- WVhat I claim is 1. A ladder having side rails and rungs extending there-between, a supporting ack permanently and pivotally mounted on said side rails for supporting a platform, a cross piece extending between said side rails be low the pivotal mounting and provided with an opening, a brace arm, an extension on said arm arranged to engage said opening for holding said jack in extended position, and a locking device associated with said cross piece for engaging said extension and locking the jack in extended position.

2. In a device of the character described, a pair of side frame members connected by a pair of vertically spaced cross-bars, one of said cross bars being rotatable; an arm on the rotatable bar, a brace pivoted to the outer end portion of the arm, and latches on said bars to engage the free ends of the arm and brace to hold them in folded position.

3. A scafi'old supporting ladder comprising a pair of interconnected [side rails, socket members on the inner faces of the rails, an upper cross bar having its ends rotatably mounted in the sockets, a lower fixed cross bar between said rails, a supporting arm having one end connected to the rotatable cross bar, a brace pivoted to the outer end portion of said arm, and means for separably connecting the free end of the brace and the lower cross bar.

4. A scaffold supporting ladder comprising a pair of interconnected side rails, socket members on the inner faces of the rails, an upper cross bar having its ends ro--.

tatably mounted in the sockets, a lower fixed cross bar between said rails, a supporting arm having one end connected to the rotatable cross bar, a brace pivoted to the outer end portion of said, arm, said;

lower cross bar having a central slot, a shouldered extension on the free end of the 'brace receivable in the slot, and a pivoted latch en a 'in the shouldered extension to a: a g

prevent accidental separation of the lower;

cross bar and brace. a

In testimony whereof I afiix my signature. c

MARTIN BAUER. 

